The O2 sensor should over ride any CO screw adjustment anyway unless things
are really off.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
neil n
Sent: Thursday, June 21, 2012 5:18 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: CO Adjusting Screw. PO Set it All The Way In? Base Setting?

Thanks Mike. 1.5 turns. Ya that rings a bell.

Adjusted CCW 3 turns. Engine warm, starting on slight incline, usual
light-foot-on-gas clutching technique, stalled 3 times in short distance.
Set to 1.75 turns, didn't stall. (oh so highly scientific)

Archives suggest an incorrectly set CO screw could damage the engine. But
since it's an idle setting, what engine damage would a too rich or too lean
idle mix do? Maybe it would happen over a long period of idle time(s).

On thesamba, someone suggested my old plugs (prior to my work) showed a rich
mix. Maybe due to a bad O2 sensor and/or 1/2 clogged cat but likely mostly
due to an incorrectly set CO adjuster.

It now surges less overall coasting in gear to a near stop. Yesterdays AFM
wiper adjustment may have helped this too.

Neil.

On Thu, Jun 21, 2012 at 12:34 PM, Mike S <mikes@flatsurface.com> wrote:

On 6/21/2012 2:36 PM, neil n wrote:
>

>  .... Checked CO screw
>> setting. It's all the way in.
>>
>
> That can't be right, unless it was adjusted to make up for a vacuum
> leak elsewhere. It's just an air bypass adjustment, to let air go past
> without being metered.
>
> Unless I have documentation otherwise, any adjustment screw which I
> know is screwed up, on any carburetor or FI system, is always "in till
> tight, out 1 1/2 turns" as a starting point. :)
>

--
Neil n

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